There is no such thing as a perfectly-made video game, especially in a free-to-play game.
As such, a game such as Combat Arms has its own share of Glitches which is defined as an exploit in the game.
If a glitch gives a player a major advantage, it will often become a frequent trend by "glitchers" throughout the game. These different faults range from people able to go through boxes to even players dying prematurely when running on stairs! Major glitches are often fixed in Patches.
In general, there are 2 main types of glitches: Exploitable and Non-Exploitable.
Exploitable glitches are those that are committed by players, hence exploitable. These include wall glitches, box glitches, etc.
Non-Exploitable glitches are in-game errors, commonly referred to as bugs. These include typos or spelling errors, faulty hit-boxes, etc.